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This story is part of the ongoing Qualcomm PR effort to get people to care about what modem is in their phones [1]. Of course no one actually makes a purchasing decision based on what modem is in their smartphone.

[1] https://www.qualcomm.com/news/onq/2018/07/23/over-million-us...

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Not sure why so many are pooh pooh'ng this. I consider the quality of display and the speed of modem two most important aspects of modern smartphones. Not everyone lives next to cell towers or in high density areas like NYC. I actually do live in NYC, but in less desirable area where avg download speed is ~2mps (Oneplus 5T on TMobile), but it was much slower and frustrating on my older phone (Note 4 on AT&T).

My service is regularly shit on America’s best network in NYC. iPhones used to be very good at this. Now I can’t make phone calls/drop in the same location, on the same cellphone.

Honestly phones supporting LAA[1] for places like penn station goes a long way toward having usable service during rush hour in a sea of people.

[1] https://en.wikipedia.org/wiki/LTE_in_unlicensed_spectrum#Lic...

LAA simply seems like the cell providers way to charge me for use of frequencies I could otherwise use for free.

A key reason I'm happy to pay cell providers so much money is because they have licenses to use lots of spectrum at high transmission powers to give me service nearly anywhere.

WiFi, it's free cousin, has lower transmission power, but in most cities one is always within range of free WiFi (even if roaming between hotspots is painful!).

When cell providers are allowed onto the free spectrum, they will use up all the available bandwidth, degrading free service and forcing users to pay for their (normally free) bandwidth.

The speed you get is far more dependent on the signal strength, not the speed of the modem. That only comes into play when you have a perfect signal, so realistically (as a perfect signal is rare), modem speed plays almost no part in speed limitations.

It does come into play in weak signal situations. Consider support for more spatial streams (4x4 mimo) helps with reception in cell edge areas and when noise levels are high or multipath interference is a factor. Also every modem/antenna pairing has limits programmed in where they'll drop a cell or switch to a different layer (band) with less bandwidth.

No iphone uses 4x4 mimo. Maybe for battery, or maybe Jony couldn't make it pleasing looking enough in the X, but its lack is very much is a factor affecting quality of service including speed in non-ideal environments.

Are there any reliable objective numbers and comparisons for this? While mimo is a great technology, it is trivial to “hold your iPhone right way” and get the same benefits, I feel mimo has become a marketing ploy for companies to push their latest without any perceptible impact to users.

Here’s some testing on the S7 with T-Mobile using 4x4: http://cellularinsights.com/samsung-galaxy-s7-the-first-4x4-...

There’s a perceptable impact to users with mimi and it specifically takes advantage of multipath. This is not a case of marketing fluff.

However, 256QAM is something you’ll probably only see in ideal situations as it requires very good signal, that’s the one that edged out gigabit speeds in the lab.

> Of course no one actually makes a purchasing decision based on what modem is in their smartphone.

I do. I have a phone I use primarily as a modem and I use some tools that lock bands so I can get more reliable speeds. As of this time I can only do this with Qualcomm chipsets.

Not that I'm a Qualcomm fanboy (being the first to comment in that this was basically their advertising) but I'm extremely wary of using Intel modems due to previous experience with their other modem chipsets sucking ass. [1]

[1] https://www.badmodems.com/index2.htm

How do you lock bands on Android?

Network signal guru on a rooted phone will do it.

Oh and there’s also qualcomm’s leaked qxdm and qpst tools for unlocking bands supported by the chipset. (and modifying stuff like carrier files for voLTE)

Didn't realise qxdm had leaked! Had to use that a lot at my last job and while it's a super powerful tool, it really provides insight into both how complex baseband systems are, and how buggy Qualcomm's firmware is. There are so many security exploits it's almost unreal.

I bought an iPhone X 100% based on the Qualcomm modem. I have the Apple store CDMA qualcomm version even tho I'm on T-mobile which had the intel version available sooner and cheaper. T-mobile service in San Francisco is absolutely terrible. Doesn't work deep inside most buildings. In the past I went through a bunch of iPhone 7's on T-mobile due to loss/theft/damage. Also compared many side by side. Some with qualcomm, some with intel, always on T-mo. Signal was a little better with qualcomm, battery life was SIGNIFICANTLY better with qualcomm. I'd guess 20-25% which is the difference between the phone dying by the end of the day or not.

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